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Search Results: 1 - 10 of 120103 matches for " Leticia; Téllez-Rojo "
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Relación entre consultas a urgencias por enfermedad respiratoria y contaminación atmosférica en Ciudad Juárez, Chihuahua
Hernández-Cadena,Leticia; Téllez-Rojo,Martha Ma.; Sanín-Aguirre,Luz Helena; Lacasa?a-Navarro,Marina; Campos,Armando; Romieu,Isabelle;
Salud Pública de México , 2000, DOI: 10.1590/S0036-36342000000400003
Abstract: objective: to assess the relationship of £10 μm particles (pm10) and atmospheric ozone concentrations, with the daily number of emergency visits due to asthma and acute respiratory diseases, among children aged under 15, living in ciudad juarez, chihuahua, mexico. material and methods: between 1998 and 1999, an ecologic study was conducted. atmospheric data were obtained from the environmental protection agency (epa), from eight monitoring stations located in ciudad juarez, chihuahua, and el paso, texas. from july 1997 to december 1998, data from emergency room visits for respiratory illness were abstracted from existing medical records of two mexican institute of social security (imss) hospitals in ciudad juarez. diagnoses were classified into two groups: a) asthma, and b) upper respiratory infections (uri), according to the international classification of diseases (icd-9 and/or idc-10). statistical analysis was carried out using the poisson regression time series method. results: during the study period, the mean 24-hour pm10 level was 34.46 μg/m3 (sd=17.99) and the mean ozone level was 51.60 ppb (sd=20.70). the model shows that an increase of 20 μg/m3 in the mean 24-hour exposure to pm10 was related to an increase of 4.97% (95% ci 0.97-9.13) in emergency visits for asthma, with a 5-day lag, as well as to an increase of 9% (95% ci 1.8-16.8) when a cumulative 5-day exposure was considered. uri increased 2.95% as a cause of emergency room visits, for each 20 μg/m3 increase in the mean 24-hour exposure to pm10. the impact of pm10 on emergency visits for asthma was greater on days with ozone ambient levels exceeded 49 ppb (median value). conclusions: a positive association was found between environmental pm10 and ozone concentrations and the daily number of emergency room visits due to asthma and acute respiratory diseases, even with levels lower than the mexican standard levels. also, a synergic effect between pm10 and o3 was found.
Relación entre consultas a urgencias por enfermedad respiratoria y contaminación atmosférica en Ciudad Juárez, Chihuahua
Hernández-Cadena Leticia,Téllez-Rojo Martha Ma.,Sanín-Aguirre Luz Helena,Lacasa?a-Navarro Marina
Salud Pública de México , 2000,
Abstract: OBJETIVO: Analizar la relación entre las concentraciones ambientales de partículas de diámetro <=10 μm (PM10) y de ozono con el número diario de consultas al servicio de urgencias por enfermedades respiratorias agudas y asma en ni os menores de 15 a os, residentes de Ciudad Juárez, Chihuahua, México. MATERIAL Y MéTODOS: Este estudio se realizó durante los a os de 1998 y 1999, utilizando un dise o de tipo ecológico. Los datos atmosféricos se obtuvieron de la base de datos de la Agencia de Protección al Ambiente (EPA), provenientes de ocho estaciones de monitoreo ubicadas en Ciudad Juárez y en El Paso, Texas. Los datos de consultas al servicio de urgencias por causas respiratorias se obtuvieron de los registros médicos de dos hospitales del Instituto Mexicano del Seguro Social (IMSS), en Ciudad Juárez, Chihuahua, de julio de 1997 a diciembre de 1998. Los diagnósticos se clasificaron en dos grupos: a) asma, y b) infecciones respiratorias altas, conforme a la Clasificación Internacional de Enfermedades (CIE-9 o CIE-10). El análisis se realizó con la utilización de la metodología de series de tiempo que emplea regresión Poisson. RESULTADOS: Durante el periodo de estudio la media de 24 horas de PM10 fue de 34.46 μg/m3 (DE=17.99) y la media de los niveles de ozono fue de 51.60 partes por billón (ppb) (DE=20.70). El modelo propuesto estima que un incremento de 20 μg/m3 en el promedio de 24 horas, en la exposición a PM10, se relaciona con un incremento de 4.97% (IC 95% 0.97-9.13) en las consultas por asma con un retraso de cinco días y con un incremento de 9% (IC 95% 1.8-16.8) cuando se considera a la exposición acumulada de cinco días anteriores. Respecto a enfermedades respiratorias altas se encontró un aumento de 2.95% en las consultas a urgencias por cada 20 μm/m3 de incremento en el promedio de 24 horas en la exposición a PM10. Se observó que el impacto de PM10 sobre las visitas de urgencia por asma fue más severo en los días en que los niveles de ozono excedían los 49 ppb (nivel de la mediana) en el ambiente. CONCLUSIONES: Se encontraron asociaciones positivas entre las concentraciones de PM10 y el número de consultas por asma y enfermedades respiratorias aun cuando los niveles alcanzados no excedían las normas ambientales mexicanas. Asimismo, se detectó un efecto sinérgico entre ozono y PM10.
Exposición al plomo y su relación con el tiempo requerido para embarazo
Guerra-Tamayo Juan Luis,Hernández-Cadena Leticia,Téllez-Rojo Martha María,Mercado-García Adriana del S
Salud Pública de México , 2003,
Abstract: OBJETIVO: Determinar los efectos de la exposición al plomo relacionados con el tiempo requerido para embarazo. MATERIAL Y MéTODOS: Entre 1997 y 2001 se realizó un estudio en 142 mujeres residentes en la Ciudad de México, participantes en un estudio de cohorte para evaluar diversos efectos del plomo sobre la salud reproductiva. Se realizaron mediciones de plomo en sangre y en hueso a cada una de las participantes en el momento de ingresar al estudio, y se obtuvo información relativa a la exposición y otras variables de interés a través de un cuestionario. A cada una de las participantes se les siguió hasta el momento en que se embarazaron, o bien, hasta el tiempo de término del estudio, con el propósito de determinar la asociación entre la exposición al plomo y el tiempo requerido para quedar embarazada. El análisis estadístico se llevó a cabo utilizando curvas de Kaplan-Meier y modelos de riesgos proporcionales de Cox. RESULTADOS: Del total de mujeres que iniciaron el estudio se embarazaron 42, de las cuales 34 lo lograron antes del primer a o de seguimiento y ocho posteriormente. Las medias de las concentraciones de plomo en sangre fueron de 9.3 μg/dl; en rótula y tibia fueron de 16.0 y 11.0 μg Pb/g de hueso mineral, respectivamente. No se detectaron diferencias en los niveles de plomo en sangre respecto al tiempo que durante el estudio requirió la mujer para embarazarse en el primer a o; no obstante, se encontró que en las mujeres con plomo en sangre por encima de 10 μg/dl el riesgo de no embarazo fue cinco veces mayor [IC 95% (1.9-19.1)] después de un a o de seguimiento, comparado con aquellas mujeres con plomo en sangre por debajo de 10 μg/dl. CONCLUSIONES: La exposición a concentraciones altas de plomo puede ser un factor de riesgo importante en el tiempo requerido para que una mujer quede embarazada, principalmente en aquellas que siendo fértiles tienen periodos mayores de un a o buscando un embarazo.
High dietary calcium intake decreases bone mobilization during pregnancy in humans
Avenda?o-Badillo,Diana; Hernández-ávila,Mauricio; Hernández-Cadena,Leticia; Rueda-Hernández,Gabriela; Solano-González,Maritsa; Ibarra,Luis G; Hu,Howard; Téllez-Rojo,Martha M.;
Salud Pública de México , 2009, DOI: 10.1590/S0036-36342009000700013
Abstract: calcium metabolism of the mother is modified during pregnancy because of the mineralization of the fetus skeleton. objective: to evaluate the association of calcium intake and bone demineralization during pregnancy. material and methods: at each trimester of pregnancy a validated food frequency intake questionnaire was administered to assess individual daily calcium intake in a cohort of 206 pregnant women, residents of mexico city. samples of urine were collected to measure levels of the cross-linked n-telopeptide of type i collagen (ntx), which is a biomarker of bone resorption. the association between calcium ingestion and bone resorption was analyzed using random effects models; non-linear associations were explored using generalized additive models. results: progressive increases in ntx levels were observed during pregnancy; with mean and standard deviation (sd) values during the first, second and third trimester of 76.50 (sd=38), 101.02 (sd=48.86) and 144.83 (sd=61.33) nmol bce/mmol creatinine, respectively. higher dietary calcium intake was associated with lower bone resorption (β=-0.015; p<0.05). the association between age and ntx showed a non-linear trend with an inflexion point around 33 years: increase in maternal age below that point was associated with a decrease in bone resorption, while in older women the increase in age was associated with an increased resorption. conclusions: our results suggest that calcium ingestion, specifically from dairy products, reduces bone resorption during pregnancy. for each 300mg (a glass of milk) of calcium intake there is an estimated reduction in ntx level of 4.8 nmol bce/mmol of creatinine (p<0.05).
Exposición al plomo y su relación con el tiempo requerido para embarazo
Guerra-Tamayo,Juan Luis; Hernández-Cadena,Leticia; Téllez-Rojo,Martha María; Mercado-García,Adriana del S; Solano-González,Maritsa; Hernández-Avila,Mauricio; Hu,Howard;
Salud Pública de México , 2003, DOI: 10.1590/S0036-36342003000800004
Abstract: objective: to determine the effects of lead exposure on the time elapsed to become pregnant. material and methods: the study population consisted of 142 women residing in mexico city between 1997 and 2001, who were already participating in a study to evaluate effects of lead exposure on reproductive health. measurements of lead in bone were performed when women were first admitted to the program. information on lead exposure and other variables of interest was obtained through a questionnaire. participants were followed up to assess the relationship between the time required to become pregnant and lead exposure. statistical analysis consisted of kaplan-meier estimates and cox proportional hazards models. results: of the total number of women in the program, 42 got pregnant: 34 before the first year of follow-up, and 8 at a later date. the mean value for lead concentration in blood was 9.3 μg/dl. the mean values for lead concentration in patella and tibia were 16.0 y 11.0 μg pb/g of bone, respectively. survival analysis was performed and no differences were detected in blood lead levels and time to pregnancy in the first year. nevertheless, in women with blood lead levels above 10.0 μg/dl, the likelihood of not achieving pregnancy was five times higher (95% confidence interval [ci] 0.05-0.56) after one year of follow-up compared with women with blood lead levels below 10.0 μg/dl. conclusions: exposure to high lead concentrations may be an important risk factor influencing the time period for a woman to get pregnant, especially in fertile women who have tried to get pregnant for more than a year.
Prevalencia de dependencia funcional y su asociación con caídas en una muestra de adultos mayores pobres en México
Manrique-Espinoza,Betty; Salinas-Rodríguez,Aarón; Moreno-Tamayo,Karla; Téllez-Rojo,Martha M;
Salud Pública de México , 2011, DOI: 10.1590/S0036-36342011000100005
Abstract: objective: to determine the prevalence of functional dependency (fd) on mexican elderly living in extreme poverty conditions and to estimate the association between falls and fd. material and methods: a survey was conducted with three stages for selection, stratified by type of locality (rural or urban) and nationally representative of the 2006 oportunidades program. the target population was composed of individuals 70 years of age and older who were beneficiaries of the oportunidades program. results: a total of 30.9% of the elderly presented fd. the gender stratified logistic regression model resulted in an odds ratio (or) for women of 1.25 (i.c:1.13-1.39) for the association between the increase in the number of falls and fd and or=1.12 (i.c:0.97-1.29) for men. conclusions: given the vulnerable conditions in which these older adults live, specific interventions need to be implemented to prevent falls in order to reduce the risk of functional dependency.
Dise?o mixto de evaluación de la iniciativa Salud Mesoamérica 2015
Gutiérrez,Juan Pablo; Téllez-Rojo,Marta María; Torres,Pilar; Romero,Martín; Bertozzi,Stefano M;
Salud Pública de México , 2011, DOI: 10.1590/S0036-36342011000900012
Abstract: since the salud mesoamerica 2015 initiative (sm-2015) aim is to improve health and nutrition conditions of those most vulnerable in mesoamerica, the goal of the evaluation is to generate evidence of the joint effectiveness of a package of interventions designed to improve the health conditions. we propose a mix design for the evaluation, which will allow to know the magnitude of changes attributable to the interventions, as well as the meanings of these changes for the target population, taking into account the specificities of each country. the main axis of this design is a locality panel where information about individuals, households, and health facilities (first and second level) will also be collected. the evaluation design described in this paper was developed between june and december, 2009, and it was integrated during workshops in cuernavaca (mexico), managua (nicaragua), and san jose (costa rica). the proposed design will allow to generate evidence about the joint effectiveness of the package of interventions proposed for the sm-2015. the success of this design rests on the political commitment of countries and donors.
Efecto del tabaquismo durante el embarazo sobre la antropometría al nacimiento
Sánchez-Zamorano,Luisa María; Téllez-Rojo,Martha María; Hernández-Avila,Mauricio;
Salud Pública de México , 2004, DOI: 10.1590/S0036-36342004000600008
Abstract: objective: to assess the effect of tobacco consumption during pregnancy on height and birth weight of newborns. material and methods: two cohort studies on lead exposure conducted in mexico city between 1993 and 2000 were analyzed. data were analyzed to assess the differences in height and birth weight between children of women who smoked during pregnancy and those who did not, adjusting for other important factors. statistical analysis consisted of multiple linear regression models. results: the proportion of women who smoked during pregnancy was 4.7%. the birth weight of children of mothers who smoked during pregnancy was 154 grams less on average (95% confidence interval [ci] -284.7, -24.7) and their height was 0.79 cm less (95% ci -1.5, -0.1) than the children of non-smokers during pregnancy. conclusions: these findings evidence the deleterious effect of tobacco consumption on children.
Pobreza, jóvenes y consumo de tabaco en México
Reddy-Jacobs,Carl; Téllez-Rojo,Martha Ma.; Meneses-González,Fernando; Campuzano-Rincón,Julio; Hernández-ávila,Mauricio;
Salud Pública de México , 2006, DOI: 10.1590/S0036-36342006000700010
Abstract: objective: to characterize tobacco use according to level of poverty in a random, nationally representative sample of adolescents (10 to 21 years old), living in urban areas with less than 50 000 inhabitants. the study was done in 2001 as part of the baseline assessment of the evaluation of the governmental program, oportunidades. material and methods: a questionnaire was applied to 29 548 adolescents living in 30 000 selected households and it included specific questions on individual tobacco use among other questions. results: the prevalence of smokers was 3.5% (95% ci: 3.3%-3.7%) and experimenters 9.9% (95% ci: 9.6%-10.2%). a logistic regression model for clustered data was constructed in order to evaluate the associated factors that distinguish a smoker from an experimenter. after adjusting for level of poverty of the household and use of alcohol and drugs, a significant association (or = 1.5, p <0.01) was found with having a paid job and a differential association was found between gender and age group. conclusions: the results of this study suggest that the additional availability of money that an adolescent has, could increase the prevalence of tobacco smoking and that the program oportunidades should include prevention campaigns directed specifically at this population group.
Peak bone mass and bone mineral density correlates for 9 to 24 year-old Mexican women, using corrected BMD
Torres-Mejía,Gabriela; Guzmán Pineda,Rubén; Téllez-Rojo,Martha María; Lazcano-Ponce,Eduardo;
Salud Pública de México , 2009, DOI: 10.1590/S0036-36342009000700011
Abstract: objective: to determine the age of peak bone mass (pbm) in mexican women and factors associated with both bmda and corrected bmd (bmdcorr) at the femoral neck and the spine (l2-l4). material and methods: data on 461 women between 9 and 24 years old was used. an interview was performed and height and weight were measured. bmda was measured by a densitometer and bmdcorr by the method proposed by kr?ger et al. (1992). results: pbm at the spine (l2-l4) was observed later than at the femoral neck. both bmda and bmdcorr at the lumbar spine correlate with age, socio-economic status, body fat percentage and height. bmda at the femoral neck correlates with overweight and obesity, body fat percentage, height and moderate physical activity; the same variables were associated with bmdcorr except for height. conclusions: the method proposed by kr?ger et al. was more precise at the femoral neck than at the spine.
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